Centrifugal pump.



P. W. KROGH.

OENTRIF UGA L PUMP.

APPLICATION FILED JULY 14, 1910.

1,1 17,861 Patented Nov. 17, 1914.

2 SHEETS-SHEET 1.

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FERDINAND W. KROGH, OF SAN FRANCISCO, CALIFORNIA.

CENTRIFUGAL PUMP.

Application filed July 14, 1910.

To all whom it may concern Be it known that I, FERDINAND W. KROGH, of San Francisco, California, have invented certain new and useful Improvements in Centrifugal Pumps, whereof the following is a specification.

This invention relates more particularly to devices for balancing the weight of the impeller and shaft, and, where the pump is driven by a motor, the armature of the motor, of a centrifugal pump.

In carrying out the invention I provide the pump with a suction chamber, preferably opposite the intake. This suction chamber connects with independent centrifugal arms, arranged between the regular impeller arms of the pump, which draw from it and create the suction therein, except when out ofl from connection therewith by the action of a valve whose operation depends upon the movement of the pump impeller in its case.

The details of the invention, and the particular manner in which I have found it best to embody it, will be best understood from the accompanying two sheets of drawing and the description thereof which follows. But it must be understood that the drawings and description are illustrative rather than specific, and that the invention is not to be limited except as set forth in the claims at the end hereof.

In the drawing:Figure 1 is an elevation of a pump, partly in section to show interior structure, and shows the impeller in its casing, the shaft and motor, the whole being mounted in a frame by which it may be handled. Fig. 2 is a view on an enlarged scale, showing in sectional elevation the impeller and casingand contiguous parts. Fig. 3 is a plan view of the impeller, one half being in section.

In the figures :1 is a frame in which the various parts are mounted, and which maintains their relation to one another.

2 is a vertical shaft, upon which is mounted the armature 3 of a motor of which 4 represents the field and 5 the casing inclosing it.

6 is a second shaft, alined with the first one 2, and rotatably connected therewith by a suitable coupling 7. Shaft 6 is below shaft 2 and supports the weight thereof, for which purpose their ends meet in the coupling. At the lower end of shaft 6 is an impeller 8 in a casing 9, of which 10 is the intake, and

Specification of Letters Patent.

Patented Nov. 117, 1914. Serial No. 572.027.

tends up into the space which the chamber- 12 occupies.

17 is a cylindrical flange in the chamber '12, extending downward towardthe impeller inside the flange 16 thereof and closely contiguous thereto so as to form a running oint therewith. At the lower edge of flange 17 is an annular inwardly projecting flange 18 which registers immediately above the ports 15 and operates as a valve to close the same when the impeller is drawn upward the desired extent by the suction in chamber 12. Theimpeller is of the type which comprlses spiral arms between two diaphragms; the upper diaphragm a registers with the opening into chamber 12 through the flange l8 and coacts therewith in regulating the position of the impeller. The leakage which comes from the discharge of the pump and finds its way between the twoflanges 16 and 17, together with leakage from the stuffing box above, will prevent the impeller being drawn up to a degree that would cause an undue friction between the movable and stationary parts.

In operation the impeller naturally tends toward the intake owing to the sucking actlon ofthe latter and the weight of the shaft, armature, &c., and the wheel itself. This movement opens the ports 15, and the auxiliary impelling arms 14 then suck from the chamber 12, and, owing to the proportions of the various parts, thereby cause the impeller to move upward. This movement brings the ports 15 against the flange 18, which closes them, and the Wheel floats in that position till the leakage relieves the vacuum in the chamber, and the wheel moves away from it to repeat the operation.

At 19 is a pressure chamber in the cas ing 9, under the impeller, and opposed to the chamber 12. This chamber 19, being open to the discharge is always under pressure,

' and therefrom drip in the bearings by gravity, thus oiling the same automatically.

Having thus described my invention, I claim is 1. In a centrifugal pumping apparatus of the vertical type in combination with the impeller thereof and its casing, a suction chamber in the casing, surrounding the shaft of the impeller opposite the intake and provided with an inwardly projecting flange having a central aperture, impelling arms provided with ports communicating with said aperture and a diaphragm on said arms .to regulate said communication.

' 2. In a centrifugal pumping apparatus of the vertical type in combination with the impeller and casing, a cylindrical flange in the casing projecting downwardly and inwardly from the edge thereof, and form.- ing a suction chamber opposite the impeller, impelling arms provided with ports communicating with said chamber, and a flange on said impelling arms projecting around said cylindrical flange in the casing and forming a running joint.

3. In a centrifugal pumping apparatus, in

. combination with the impeller and casing,

a suction chamber adapted to draw the impeller toward one slde of the casing,.impelling arms communicating with said champlay of thejmpellen.

what

her, a flange Within said chamberprojecting inwardly: from'the edge thereof "to provide means for varying the opening from. said chamber to said armswithflthe lat ral,

4. In a centrifugal "pumping ap. aratus,j in combination with the impeller and ca's ing, a suction chamber at one side of the, casing impelllng arms communicating with said chamber, a cylindrical flange on the casing in said chamber, and an annular inwardly projecting flange on the edge of said cylindrical flange, said annular flange in register with the ports from the chamber into the arms and adapted to vary the opening into the same with the lateral play of the impeller. j 5. In a centrifugal pumping apparatus, in combination with the impeller thereof and its casing, a cylindrical flange projecting# from the casing toward the side of the impeller and forming a suction chamber, an

annular inwardly projecting flange on the edge of said cylindrical flange, impelling arms provided with ports communicating with the suction chamber and adapted to be closed by said inwardly projecting flange. 6. ln a centrifugal pumping apparatus, of the vertical type, in combination with the impeller thereof and itscasing, an open suction chamber in the casing above the impeller and opposite the intake, and impelling arms having a diaphragm adapted to close said chamber;

In testimony have hereto set my July, 1910, in the presence of witnesses.

FERDINAND W. KROGH.

Witnesses: Y

W. S. Barns, H. P. DWYER.

that I claim the foregoing I 

